W. Jack Rejeski’s research while affiliated with Wake Forest University and other places

Background Prior work shows caloric restriction (CR) can improve physical function among older adults living with obesity. However, the contribution of starting weight and inflammatory burden to CR-associated functional improvements is unclear. The primary purpose of this study was to determine if CR-associated gait speed change varied by body mass index (BMI) and plasma interleukin 6 (IL-6) at baseline and secondarily to determine the contribution of BMI change and IL-6 change to gait speed change.Design, Setting, ParticipantsData from eight randomized control trials were pooled, with 1184 participants randomized to CR (n=661) and No CR (n=523) conditions. All studies assessed outcomes before and five or six months after assignment to CR or No CR.MeasurementsBMI and IL-6 were assessed at baseline using standard procedures. Gait speed was assessed with the six-minute walk test or 400m walk test. Baseline BMI/IL-6 subgroups were constructed using BMI≥35 kg/m2 and IL-6>2.5 pg/mL thresholds. Participants with BMI≥35 kg/m2 were grouped into class 2+ obesity and BMI<35 kg/m2 into class 1- obesity; IL-6>2.5 pg/mL were grouped into high IL-6, and <2.5 pg/mL as low IL-6 (class 2+ obesity/high IL-6: n=288, class 2+ obesity/low IL-6: n=143, class 1- obesity/high IL-6: n=354, or class 1- obesity/low IL-6: n=399). All analyses used adjusted general linear models.ResultsGait speed significantly improved with CR versus non-CR [mean difference: +0.02 m/s (95% CI: 0.01, 0.04)]. CR assignment significantly interacted with BMI/IL-6 subgroup membership (p=0.03). Greatest gait speed improvement was observed in the class 2+ obesity/high IL-6 subgroup [+0.07 m/s (0.03, 0.10)]. No other subgroups observed significant gait speed change. For each unit decrease in BMI, gait speed change increased by +0.02 m/s (p<0.001; R2=0.26), while log IL-6 change did not significantly affect gait speed change [+0.01 m/s (p=0.20)].Conclusions Only the class 2+ obesity/high IL-6 subgroup significantly improved gait speed in response to CR. Improvement in gait speed in this subgroup was driven by a larger decrease in BMI, but not IL-6, in response to CR. Individuals with class 2+ obesity and high IL-6 are most likely to show improved gait speed in response to CR, with improvement predominantly driven by reductions in BMI.

Background This report investigates the impact of a remote physical activity intervention on self-efficacy, satisfaction with functioning, and health-related quality of life (HRQOL) as assessed by the SF-36 in obese older adults with chronic pain. The intervention was group-mediated in nature and based in social cognitive theory and mindfulness-based relapse prevention.Methods Participants (N = 28; 70.21 ± 5.22 years) were randomly assigned to receive either the active intervention, which focused on reducing caloric intake and increasing steps across the day or to a waitlist control condition.ResultsOver 12 weeks, intervention participants reported a moderate, positive improvement in self-efficacy for walking relative to control. They also reported large magnitude improvements in satisfaction for physical functioning as well as improvements on pain and the physical functioning subscales of the SF-36.Conclusions These findings expand on previous research showing similar effects in response to structured exercise, this time via a protocol that is likely to be scalable and sustainable for many older adults. Additional work on larger and more diverse samples is warranted.

The purpose of this study was to examine the relationships between university students’ respiratory sinus arrhythmia (RSA) profiles and both retrospective and momentary ratings of stress. Participants were undergraduate students enrolled in an introductory health science course (N = 64). Participants provided RSA data at rest (tonic) and following an orthostatic challenge (phasic), completed the 10-item Perceived Stress Scale (PSS), and completed 6 daily ecological momentary assessments (EMA) of stress for 1 week. Higher tonic RSA was associated with lower perceived stress assessed via PSS and average EMA responses. Those with higher tonic RSA did not differ in their experience of stress across the week, whereas those with lower tonic RSA experienced increased stress across the week, and these trajectories varied as a function of phasic responses. These findings suggest a need for greater emphasis on behavioral strategies for maintaining and enhancing autonomic nervous system health among college students.

Promoting lasting weight loss among older adults is an important public health challenge. Participation in physical activity aids in weight loss and is important for the maintenance of physical function and quality of life. However, traditional intensive lifestyle interventions place a focus on discrete bouts of structured activity, leaving much of the remainder of the day for sedentary behavior. Structured exercise and weight loss programs often produce short-term weight loss that is typically followed by weight regain, and older adults are more likely to regain weight as fat mass rather than lean mass. Preliminary evidence suggests a focus on day-long movement intended to minimize time spent sitting produces better short-term weight loss and weight maintenance. Herein we describe the design and methods for a three-arm randomized controlled trial comparing mHealth-supported weight loss (WL) + structured exercise (EX); WL + a novel daily movement intervention (SitLess); and WL + EX + SitLess. Older adults (N = 180) will be randomly assigned to one of the three interventions, each comprised of a 6-month intensive phase; a 3-month transition phase; and a 9-month maintenance phase. The primary aim of the study is to determine whether the addition of SitLess to a traditional intensive lifestyle intervention comprised of dietary weight loss and structured exercise produces a larger 18-month reduction in body weight relative to WL + EX and WL + SitLess.

Background Stress is a known factor related to alcohol use. However, how the relationship between alcohol craving and stress varies across the day is not fully understood. As craving is a consistent predictor of alcohol use disorder (AUD), understanding stress and craving patterns across the day in routine, non-dependent, moderate-heavy alcohol consumers may help in understanding those who may be vulnerable to transitioning into AUD. Method Moderate-heavy drinkers were recruited from the local community (n = 32) and assessed for fluctuations in craving and stress intensity across the day via Ecological Momentary Assessment (EMA) during 3 consecutive days of imposed alcohol abstinence (abstained trial) and their normal drinking routine (normal trial). A multilevel modeling statistical approach assessed differences in diurnal craving and stress patterns with the Alcohol Craving Experience Questionnaire (ACE) examined as a moderator. Results Immediately following alcohol consumption on normal trials, EMA craving levels were significantly reduced compared to pre-drinking levels. Moreover, the post-drinking craving levels were lower than on abstained trials. Higher ACE scores were associated with significantly higher EMA craving across the day and higher peaks at midday. Higher ACE scores were also associated with greater EMA stress across the day. Drinking relieved stress relative to abstained trials, but not in individuals with higher ACE scores. Higher stress was associated with greater EMA craving, which was stronger among those with higher ACE scores. Conclusion These findings suggest that ACE scores are important to understanding patterns of stress and craving experienced across the day in routine, non-dependent, moderate-heavy drinkers and may provide new insights for vulnerability to transitioning into AUD.

Weight loss interventions present a unique challenge in older adults: relative loss of lean mass during weight loss, if superimposed on age-related sarcopenia may increase the risk for mobility disability. Relative loss of lean mass (25-30%) during weight loss depends on the severity/duration of caloric restriction, initial body mass, and concomitant exercise training. We hypothesized that subclinical imbalances of acid-base status (reflected in lower serum bicarbonate) may also affect relative loss of lean mass during weight loss. The rationale: even subtle imbalances of acid-base status (e.g. bicarbonate <23 mmol) impact clinical outcomes in older adults such as gait speed or incidence of functional limitation, while bicarbonate supplementation reduces urinary nitrogen wasting and may improve physical function. However, data on acid-base balance and serum bicarbonate during moderate caloric restriction are lacking. We, therefore, analyzed 2 randomized, controlled weight loss trials (including moderate caloric restriction and exercise): The Diet, Exercise, and Metabolism for Older Women [DEMO; (58±5.2 y)] and Cooperative Lifestyle Program; [CLIP; (67±4.7 y)]. Serum bicarbonate was assessed as total CO 2 (in mmol) and whole body lean mass measured by dual-energy X-ray absorptiometry. The analysis showed that 48% of participants had bicarbonate <23. DEMO participants with lower serum bicarbonate at baseline lost more lean mass during the intervention (unadjusted β(SE)=0.32(0.16); p=0.04; n=92). Adjustments for age, BMI, eGFR, % weight loss, baseline, intervention group, had little effect, but adjusting for protein intake during weight loss attenuated the association (β(SE)=0.17(0.15); p=0.28.). Similarly, a change in serum bicarbonate during the trial was associated with % lean mass change, but attenuated after controlling for protein intake. This is not unexpected: protein is acid-producing and one of two major determinants of net dietary acid load; higher dietary acid load correlates with lower serum bicarbonate, in older adults. Results from the CLIP trial were remarkably similar, and consistently, baseline serum bicarbonate level was marginally predictive of baseline daily protein intake, with highest baseline serum bicarbonate having the lowest protein intake [bicarbonate: >24 (n=58); >21-24 (n=121); <21 (N=93); protein in g/kg body weight 0.7(0.4); 0.9(0.4); 0.8(0.4) respectively, p=0.057). In conclusion, our analysis suggests that higher serum bicarbonate before and during weight loss may ameliorate loss of lean mass, however, to obtain definitive answer such analysis needs to be conducted under conditions of controlled or randomized protein intake. Importantly, our findings suggest that oral bicarbonate supplementation, a simple and relatively safe intervention, may ameliorate loss of lean mass during weight loss interventions in older adults.

Background: Limited evidence suggests that physical activity may prevent frailty and associated negative outcomes in older adults. Definitive data from large long-term randomized trials are lacking. Objective: To determine whether a long-term, structured, moderate-intensity physical activity program is associated with a lower risk for frailty and whether frailty status alters the effect of physical activity on the reduction in major mobility disability (MMD) risk. Design: Multicenter, single-blind, randomized trial. Setting: 8 centers in the United States. Participants: 1635 community-dwelling adults, aged 70 to 89 years, with functional limitations. Intervention: A structured, moderate-intensity physical activity program incorporating aerobic, resistance, and flexibility activities or a health education program consisting of workshops and stretching exercises. Measurements: Frailty, as defined by the SOF (Study of Osteoporotic Fractures) index, at baseline and 6, 12, and 24 months, and MMD, defined as the inability to walk 400 m, for up to 3.5 years. Results: Over 24 months of follow-up, the risk for frailty (n = 1623) was not statistically significantly different in the physical activity versus the health education group (adjusted prevalence difference, -0.021 [95% CI, -0.049 to 0.007]). Among the 3 criteria of the SOF index, the physical activity intervention was associated with improvement in the inability to rise from a chair (adjusted prevalence difference, -0.050 [CI, -0.081 to -0.020]). Baseline frailty status did not modify the effect of physical activity on reducing incident MMD (P for interaction = 0.91). Limitation: Frailty status was neither an entry criterion nor a randomization stratum. Conclusion: A structured, moderate-intensity physical activity program was not associated with a reduced risk for frailty over 2 years among sedentary, community-dwelling older adults. The beneficial effect of physical activity on the incidence of MMD did not differ between frail and nonfrail participants. Primary funding source: National Institute on Aging, National Institutes of Health.

Background: For older adults, hospitalization confers functional loss, which in turn increases hospitalizations. Physical function screening may identify an at-risk population for early intervention. The Mobility Assessment Tool – short form (MAT-sf) is a brief, innovative, avatar-based self-report tool that predicts mobility disability. This study explored whether baseline MAT-sf score is associated with number of hospitalizations and time to first hospitalization. Design: Post-hoc analysis of prospectively-gathered data from the Lifestyle Interventions and Independence for Elders (LIFE) Study, a randomized clinical trial of lifestyle interventions to preserve mobility in older adults, conducted in eight U.S. academic medical centers. Participants: Among 1635 sedentary community-dwelling older adults enrolled in LIFE, 1574 completed baseline physical function screening including MAT-sf, with scores ranging from 30.2 (low function) to 69.8 (high function). Measurements: Number of hospitalizations and time to first hospitalization, adjusted for age, gender, race, living alone, clinical site, and baseline comorbid conditions, # prescription medications, and cognition. Results: Of the 1557 participants with hospitalization data, 726 (47%) experienced at least one hospitalization, with the majority (78%) of these experiencing 1–2 hospitalizations. For every 10-point increase in MAT-sf defined mobility, there was a 16% decreased rate of all hospitalizations (adjusted rate ratio 0.84, 95% CI: 0.76 to 0.93, p< 0.001). Higher baseline MAT-sf scores were also associated with a decreased risk of first hospitalization (adjusted Hazard Ratio 0.83, 95% CI: 0.76 to 0.92, p< 0.001, per 10-point increase in MAT-sf). Conclusion: MAT-sf may identify older adults at increased risk for hospitalizations, who may benefit from care coordination.

Within the past 10 years, our research group has used Animated Video Technology as a means of enriching assessment stimuli when evaluating various aspects of physical function. This session focuses on the mobility assessment tool-short form (MAT-sf) and also briefly illustrates how we have applied this methodology to a virtual assessment of the SPPB and in evaluating physical activity behavior. The MAT-sf has excellent content validity and reliability—an ICC = 0.93. Within the LIFE study, we recently showed that rates of 24-month major mobility disability were 51% for those within the lowest quartile of the MAT-sf and just 10% for those with the highest quartile. Furthermore, the MAT-sf has been found to be predictive of post-surgical complications including length of hospital stay and rates of nursing home placement.

The objective of the present study was to compare a group-mediated cognitive behavioral (GMCB) physical activity intervention with traditional exercise therapy (TRAD) upon select social cognitive outcomes in sedentary knee osteoarthritis (knee OA) patients. A total of 80 patients (mean age = 63.5 years; 84% women) were recruited using clinic and community-based strategies to a 12-month, single-blind, two-arm, randomized controlled trial. Mobility-related self-efficacy, self-regulatory self-efficacy (SRSE), and satisfaction with physical function (SPF) were assessed at baseline, 3, and 12 months. Results of intent-to-treat 2 (Treatment: GMCB and TRAD) × 2 (Time: 3 and 12 month) analyses of covariance yielded significantly greater increases in SRSE and SPF (P < 0.01) relative to TRAD. Partial correlations revealed that changes in SRSE and SPF were significantly related (P < 0.05) to improvements in physical activity and mobility at 3 and 12-months. The GMCB intervention yielded more favorable effects on important social cognitive outcomes than TRAD; these effects were related to improvements in physical activity and mobility.